Introduction: To determine if a relatively inexpensive ($895) mechanical birth simulator is effective for teaching third year medical students about normal labor and delivery and to evaluate its effect on their confidence to perform a vaginal delivery. Simulators have been shown to improve student confidence and knowledge during obstetric clerkships.
Methods: This was an observational trial of thirty-nine medical students rotating through their obstetrics, gynecology and women’s health clerkship at an academic medical center who participated in an educational innovation using a mechanical birth simulator. Obstetric knowledge and confidence were measured pre- and post-simulation training using questionnaires.
Results: Forty-three students were approached about participating in an educational innovation. All agreed to participate. Thirty-nine had complete pre- and post-simulation training questionnaires and were therefore included in the analysis. The majority (39) were third year medical students; four were fourth year subinterns. Twelve had completed their labor and delivery rotation, 28 were currently on the rotation and three students had not yet had any labor and delivery experience. Thirty-nine of the 43 (90.7%) students completed pre- and post-simulation training questionnaires and were included in the analysis. Simulator training resulted in an improvement in obstetrical knowledge on all questions asked (P < 0.001) and an improvement in student confidence for all scenarios presented ( P < 0.001).
Conclusion: A simple mechanical birth simulator is practical, engaging and cost-effective for teaching third year medical students about normal labor and delivery. It resulted in improved student knowledge and confidence.
Simulation training has emerged as a novel teaching solution in third year medical student clerkship training. Simulation can allow for a risk free experience, repeated practice and learning prior to working with patients. Simulator training has been shown to improve medical student confidence in their abilities to perform a vaginal delivery [1-3]. Simulation has also been shown to improve oral and written exam scores for third year medical students , and to increase participation in deliveries during the third year clerkship . However, all but one of these studies exclusively used an electronic birth simulator. The cost of electronic simulators ranges from several thousand to tens of thousands of dollars which may limit their widespread use in undergraduate medical teaching. The purpose of our study was to determine if the use of less expensive, simpler, mechanical birth simulator could similarly increase student confidence and knowledge about normal vaginal delivery.
We were selected to receive a 2013 Try It! Summer Mini-Grant through the Paul C. Reinert, S.J. Center for Transformative Teaching and Learning At St. Louis University. These grants of up to $1,500 are intended to fund small-scale pedagogical projects that can have an immediate impact on student learning and engagement at St. Louis University. With this funding we purchased a plastic model of the bony pelvis and a model fetus. Additionally, we obtained a model torso/pelvis that can simulate labor and delivery (S500.100 Ob Susie, Gaumard, Miami, FL). Total cost before shipping and handling $1,036 which included the female pelvic skeleton ($77), model fetus ($64) and light weight birthing torso ($895). This study was approved by the St. Louis University Institutional Review Board as exempt.
Medical students participating in the obstetrics and
gynecology rotation at SSM Health St. Mary’s Hospital from July to
December 2013 were asked if they were willing to
participate in the educational initiative. The participants were
a convenience sample of available students. They were divided
into groups of 3-5 students for 1.5-2.5 hour sessions. The models
were used to teach pelvic anatomy, the cardinal movement
of labor, and provide a simulation of labor and delivery. Each
student went through the process of delivery with the model
bony pelvis and the mechanical torso model. To evaluate the
success of the new teaching tool, we used a standardized
questionnaire to test student knowledge of the stages of labor,
types of obstetric lacerations, and the cardinal movements of
labor. All questionnaires were anonymous with no identifying
name or date. Students were told the questionnaires had no
bearing on their evaluations for the rotation. The questionnaires
were administered before and after the simulation exercise to
measure the effects of the simulation. Additionally, the students
were asked about their knowledge and readiness to participate
in a delivery before and after the simulation. This was based
on previously published studies of the use of a simulator [1,4].
Finally, a questionnaire was given to evaluate how useful the
medical students found the simulation exercise.
Questions assessing knowledge of the stages of labor, types
of obstetric lacerations, and cardinal movements of labor were
open-ended questions where students were asked to write in
their answers. The number of correct answers was compared
between the pre- and post-simulation questionnaire. A student
had to correctly define all three stages of labor, all four types of
obstetric lacerations, and all cardinal movements of labor to be
coded as a correct answer. Partially correct answers were coded
as incorrect. Changes in knowledge of stages of labor, types of
obstetric lacerations, and cardinal movements of labor were
assessed using McNemar’s test. Student self-confidence in their
knowledge of the stages of labor and the cardinal movements
of labor and readiness to participate in a vaginal delivery with
and without supervision were measured on the pre- and postsimulation
questionnaire with a 5-point scale: strongly agree,
somewhat agree, neutral, somewhat disagree, and strongly
disagree. This 5-point scale was transformed into a Likert scale
with the respective values of 2, 1, 0, -1, -2. Changes in the Likert
scale pre- and post-simulation measurements were assessed
using the Wilcoxon Signed Rank test due to a lack of normality of
the distributions. The students also completed a post-simulation
assessment of the efficacy of the simulation training using the
same 5-point Likert scale. A p-value of < 0.05 was used to denote
statistical significance. All analyses were performed using SPSS
version 23.0 for Windows.
From July to December 2013, 84 third year medical students
rotated through the obstetrics and gynecology clerkship. This
was the time period for the educational intervention supported
by the Try It! Summer Mini Grant project. Forty-three students
were approached about trying the new simulator educational
session and all agreed to participate. Four were removed
from the analysis because of incomplete data on the post-test
questionnaire. All four missed the back page and left it blank.
Therefore, 39 students had complete data available for analysis
of pre- and post -simulation assessment of knowledge and
confidence. The majority of the students were third year medical
students, four were fourth year subinterns. Twelve had already
participated in their labor and delivery rotation, 28 were in
the middle of that rotation and three had not yet started it. All
students were analyzed together.
*Four students were not included in the analysis due to missing post-simulation training data on all three questions. † McNemar’s Test
Median value on a 5 point scale: strongly agree (2), agree(1), neutral(0), disagree(-1), strongly disagree(-2), and range. Wilcoxon signed rank test.
Changes in knowledge of stages of labor, types of obstetric
lacerations, and cardinal movements of labor between the preand
post-simulation questionnaire are given in Table 1. All
three questions showed a statistically significant improvement
post-simulation. Similarly, all questions assessing student selfconfidence
in knowledge of stages of labor, knowledge of cardinal
movements of labor, and readiness to participate in a vaginal
delivery with and without supervision showed a statistically
significant improvement on the post-simulation questionnaire
(Table 2). Students were very supportive in their evaluation of the
simulation training (Table 3). All students strongly agreed that
the simulation was helpful. All students either strongly agreed or
somewhat agreed that the simulation helped them understand
the process of labor and to understand pelvic anatomy. Most
students felt that a lecture would not have provided the same
education. Finally, all students thought that the labor simulation
should be continued as part of the third year medical curriculum
The use of a simple and relatively inexpensive birth simulator
is a readily available solution to the problems of patient access
and liability concerns during undergraduate medical education.
We wanted to see if a simple, inexpensive labor simulator could be used to instruct medical students. This study demonstrates that
it is an effective method of teaching third and fourth year medical
students during their obstetrics and gynecology clerkships.
The students had significant improvement in their knowledge
of all areas assessed. Additionally, their own assessment of
their knowledge and skills was significantly improved postsimulation.
Finally, they uniformly felt the exercise was valuable.
Previous studies have shown similar results though most used
more elaborate, more expensive, electronic simulators [1,3,4].
Simulators have consistently resulted in increased student
knowledge and confidence though their use is relatively new.
The high cost of electronic, automated, high fidelity simulators
may have limited their widespread adoption. Our study shows
that a simple, low fidelity mechanical birthing simulator is an
effective teaching tool that was well received by the students.
The primary strength of our study is that our data show
consistent improvements in all measures of knowledge and
confidence with the use of the simulator. Furthermore, in our
post-simulation survey, the students felt they learned more by
using the simulator than a lecture alone would have offered.
Their written comments were uniformly positive. Our study
has several limitations. We had a relatively small sample size.
Secondly, there was no control group of students who did not
participate in the educational initiative. We only assessed
those who tried the new simulator. Additionally, in the student
population there were varying degrees of prior obstetrical
knowledge depending on their past rotations, which could have
biased the results. The same attending physician administered
the examinations and performed the simulation training, which
could have potentially biased the study. We tried to minimize
this by clear instructions and collecting no identifying data or
dates on the surveys. Simulator training is being used more and
more in graduate medical education. It provides a hands-on way
to learn complex interventions with no risk to the patient, while
providing a forum for feedback and improvement. We believe it
should be routinely used for undergraduate medical education,
too. This study adds to the growing literature that shows its
efficacy. Our data show that a simple and inexpensive mechanical
model can significantly enhance medical student learning.